Involvement of the Gut Microbiota in Calcified Aortic Stenosis

Launched by INSEL GRUPPE AG, UNIVERSITY HOSPITAL BERN · Aug 29, 2023

Keywords

ClinConnect Summary

This clinical trial is studying the relationship between the gut microbiota—tiny microorganisms living in our intestines—and calcific aortic stenosis (CAS), a condition where the aortic valve in the heart becomes stiff and narrowed due to calcium buildup. This condition is common in older adults and can severely affect blood flow. The researchers aim to better understand how the gut microbiota might influence the development of CAS by comparing the gut bacteria of patients with CAS to those who are healthy. They hope to discover specific molecules produced by these microorganisms that could be linked to the disease.

To participate in this study, you need to be between the ages of 65 and 75 and have a diagnosis of calcific aortic stenosis based on recent heart imaging tests. If you do not have this condition, you may be eligible to join the control group for comparison. Participants will undergo tests to analyze their gut bacteria and the substances these bacteria produce. It's important to note that certain medications and health conditions may exclude individuals from joining the trial. The goal is to find new insights into CAS, which could lead to better prevention and treatment options in the future.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• * Group of patients with CAS:
• • Calcified aortic stenosis diagnosed on a cardiac ultrasound or CT not older than 3 months
• • Severe aortic stenosis: surgical indication based on symptoms and ultrasound data (high gradient aortic stenosis : Vmax\> 4m/s, mean gradient \> 40mmHg, area \< 1cm², low flow low-gradient CAS: left ventricular ejection fraction (LVEF) \< 40%, Vmax\< 4m/s, mean gradient \< 40mmHg, area \< 1cm², paradoxical low-gradient CAS: LVEF \> 55%, Vmax\< 4m/s, mean gradient \< 40mmHg, area \< 1cm²)
• • Moderate CAS: 3m/s \<Vmax\< 4m/s, 20mmHg \< mean gradient \< 40mmHg
• • Mild CAS: 2,6m/s \< Vmax \< 2.9m/s, mean gradient \< 20mmHg
• • Aortic sclerosis: calcified remodeling of the aortic valve visible on ultrasound or CT.
• Control group - free of CAS:
• • - No calcified aortic stenosis verified on a cardiac ultrasound or CT not older than 3 months
• Exclusion Criteria:
• • Treatment interfering with the composition of the intestinal microbiota: local or systemic corticosteroids within the last 3 months, antibiotics within the last 3 months, antiretrovirals, bile acid chelators (questran and colesevelam), HIV-targeted antiretroviral therapies, selective serotonin reuptake inhibitor-type antidepressants
• • Clinical criteria: history of cholecystectomy, documented chronic liver disease in the patient, failure to fast on the day of the blood test, inflammatory bowel disease
• • Patients requiring emergency intervention (myocardial infarction, acute aortic or mitral insufficiency, cardiogenic shock).
• • AS of rheumatic origin, infective endocarditis.